The recent emergence of thin-film lithium niobate (TFLN) has extended the landscape of integrated photonics. This has been enabled by the commercialization of TFLN wafers and advanced nanofabrication of TFLN such as high-quality dry etching. However, fabrication imperfections still limit the propagation loss to a few dB/m, restricting the impact of this platform. Here, we demonstrate TFLN microresonators with a record-high intrinsic quality (Q) factor of twenty-nine million, corresponding to an ultra-low propagation loss of 1.3 dB/m. We present spectral analysis and the statistical distribution of Q factors across different resonator geometries. Our work pushes the fabrication limits of TFLN photonics to achieve a Q factor within 1 order of magnitude of the material limit.

中文翻译：

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薄膜铌酸锂上的 2900 万个本征 Q 因子单片微谐振器


最近出现的薄膜铌酸锂（TFLN）扩展了集成光子学的前景。这是通过 TFLN 晶圆的商业化和先进的 TFLN 纳米加工（例如高质量干法蚀刻）实现的。然而，制造缺陷仍然将传播损耗限制在几个 dB/m，从而限制了该平台的影响。在这里，我们展示了具有创纪录的高内在质量的 TFLN 微谐振器（问）系数为 2900 万，对应于 1.3 dB/m 的超低传播损耗。我们提出了光谱分析和统计分布问不同谐振器几何形状的因素。我们的工作突破了 TFLN 光子学的制造极限，以实现问系数在材料极限的 1 个数量级内。